Antago-3 is a synthetic peptide with a molecular weight of 1172.47, which is an oxytocin analog with a powerful and specific oxytocin antagonism effect (WO94/25485-A).
Physiologically active peptides readily undergo enzymolysis by peroral or permucosal administration, while they are virtually unabsorbed by percutaneous administration due to their low membrane permeability, and hence they are generally administered in the form of injections.
For permucosal administration of physiologically active peptides, expression of their drug effects has required a method whereby an enzyme inhibitor or protective substance is added to protect the drugs from enzymes, or a method whereby an absorption enhancer is added to promote absorption of the drugs before their degradation.
As permucosal preparations of physiologically active peptides there are known preparations containing cyclodextrin (Japanese Patent Publication No. 19092 of 1990), preparations containing bile acid (Japanese Patent Publication No. 25068 of 1994, Japanese Laid-open Patent Publications No. 2932 of 1988 and No. 194260 of 1993), preparations containing surfactants (Japanese Laid-open Patent Publications No. 130820 of 1984 and No. 185030 of 1987), preparations containing absorption accelerators (Japanese Laid-open Patent Publications No. 267528 of 1986 and No. 196524 of 1988), preparations containing sucrose fatty acid esters (Japanese Laid-open Patent Publications No. 39822 of 1988, No. 214 of 1990 and No. 101020 of 1990), preparations containing saccharides (Japanese Laid-open Patent Publication No. 502920 of 1991) and preparations containing ethylenediamine tetraacetate (Japanese Laid-open Patent Publication No. 306921 of 1990), but no permucosal preparation is known that contains Antago-3 or a physiologically acceptable salt thereof as an effective component.